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Ti3C2TxMXene membranes have attracted considerable interest due to their exceptional water transport properties, yet the role of cation intercalation on governing transport remains poorly understood. In this experimental and theoretical study, it shows how intercalation with K+, Na+, Li+, Ca2+, and Mg2+modulates both the nanochannel architecture and water flux of Ti3C2Txmembranes. Unlike in graphene oxide analogs, cations with larger hydration diameters in Ti3C2Txexpand the interlayer spacing, widening flow channels, enhancing slip length of these nanochannels, and boosting water flux from 31.45 to 61.86 L m−2 h−1. To overcome intrinsically poor adhesion of Ti3C2Txto polymeric supports, this study incorporates a thin polyvinyl‐alcohol interlayer, which substantially enhances mechanical robustness and structural integrity. Together, these findings elucidate how cation hydration controls water transport and offer a flexible strategy for tailoring MXene membrane performance.
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This content will become publicly available on November 27, 2025
Intercalation of Polyacrylonitrile Nanoparticles in Ti 3 C 2 T x MXene Layers for Improved Supercapacitance
We report the intercalation of polyacrylonitrile nanoparticles in Ti3C2Tx MXene layers through simple sonication. The use of polyacrylonitrile, which was synthesized via radical polymerization, offered dual benefits: (1) It increased the interlayer spacing of MXene, thereby exposing more surface area and enhancing ion transport channels during charge and discharge cycles, and (2) Integrating MXene with polyacrylonitrile enables the creation of a composite with conductive properties, following percolation principle. X-ray diffraction analysis showed an increase in the c-lattice parameter, indicative of the interlayer spacing, from 22.31 Å for the pristine MXene to 37.73 Å for the MXene−polyacrylonitrile composite. The intercalated polyacrylonitrile nanoparticles facilitated the delamination by weakening the interlayer interactions, especially during sonication. Electrochemical assessments revealed significant improvement in the properties of the MXene−polyacrylonitrile composite compared to the pristine MXene. The assembled asymmetric device achieved a good specific capacitance of 32.1 F/g, an energy density of 11.42 W h/kg, and 82.2% capacitance retention after 10,000 cycles, highlighting the practical potential of the MXene−polyacrylonitrile composite.
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- Award ID(s):
- 1800795
- PAR ID:
- 10562233
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Applied Materials & Interfaces
- Volume:
- 16
- Issue:
- 47
- ISSN:
- 1944-8244
- Page Range / eLocation ID:
- 64784 to 64796
- Subject(s) / Keyword(s):
- MXenes polymer nanocomposites supercapacitor energy storage
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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